How is the auditory system affected by the occlusion effect?

The occlusion effect refers to the phenomenon that occurs when sounds are blocked from reaching the ear canal, often caused by the use of hearing aids or earplugs. When this occlusion occurs, individuals may experience a heightened perception of the loudness of their own voice. This is because, when the ear canal is occluded, the vibrations produced by the voice are trapped and resonate more in the closed ear canal, leading to an amplified perception of sound.

In contrast, the other choices do not accurately describe the occlusion effect. The enhancement of sound localization is not typically associated with the occlusion effect; in fact, occlusion can sometimes impair localization ability because important auditory cues are blocked. Similarly, the volume of external sounds is not increased as a direct consequence of occlusion; rather, it may change the quality or clarity of those sounds. As for the overall hearing sensitivity, the occlusion effect is not known to decrease it; instead, it can alter the way sounds are perceived, particularly the sounds generated internally, like one's own voice.